Jimenez's homer off GreenJackets starter T.J. Brewer put Savannah up 3-0 in the fourth inning. The Sand Gants added their final run on Casey Craig's RBI single in the eighth.
Brewer (3-4) worked six innings, allowing three runs on six hits while walking one and striking out two. He got no help from his offense, which stranded runners on base in the fifth and sixth innings.
The GreenJackets (32-23) fell to the Sand Gnats (24-31) for the second night in a row. They'll try to split the four-game series at 2 p.m. today.
Augusta will send lefty Craig Clark (4-0, 4.27) to the mound against Savannah southpaw Mike Antonini (4-2, 2.51).